Photographic emulsions sensitized with supersensitizing combinations of acid carbocyanine dyes and styryl bases



Dec. 12, 1950 B. H. CARROLL ET AL 2,533,426

PHoTosRAPHc EMULsIoNs SENSITIZED WITH s uPERsENsITIzING COMBINATIoNs oFACID cARBocYANNE DYEs AND sTYRYL- BASES Filed oct. 1s, 194s FIG.Z.

FIG. 3.

BURT H. CARROLL JOHN SPENCE INVENTORS 4 TTORN S Patented Dec. 12, y1950y UNITED STAT-Es PATENT .lorries PHOTOGRAPHIC EMULSIONS SENSITIZED WITHSUPERSENSITIZING 'CQMBNA- TI'ONS OF ACID CARBG'CYNINE lDYE-S AND STYRYLBASES Burt Carroll and John Spence, ,-Rochesten Xs .assignors to EastmanKodak Company, Rochester, N. Y., a corporation of :New ,Jersey 2 Thisinvention relates to photographic emulfrom the -group consisting .of-COO- and sions lsensitized -witha supersensi-tizing fconibina- S0201 R.represents a member selected from tion of -a-cid carbocya-nine -dyes andstyryl bases, the group 'consisting 'o'f ahydrgen atom, amethyl andi-tpaprocessiforpreparingitheesame, group rand an ethyl; group, R1represen-ts a pri- I-t l'is known that styryl 'ibases supersensitize 5mary 'alkylgroup ofthe formula Cdl-laser wherein basic monomethinecyan-ine dyes and, to a lesser d 'represents waposi-tive"integer fromrv-1 to'4,'X repextent, basic carbocyanine dyes and basic hemiresents ananion, Z represents the Vvnon-metallic diCaIbOCyanDe dyes. :See -UnitedStates Patents atoms necessary .to complete a heterccyclic n-u-2,313,922A, dated March 16, 1943, and 2,316,268, cleussele'cted from thegroup consist-ing olf hetdated April l16, 1943,. It is also known thatacid 10 erocyclic nuclei of the benzothiazole series and and 'basic'sensitizingdyes are relatively ncomheterocyclic nuclei of thea-naphthoth'iazole sepati'ble; Yfor example, sensitization "bym-cans ofries and iZi represents `the non-metallic :atoms `oo n'lbinations ofeosin dyes and oy'anine dyes vlis necessary to ycomplete a heterocyclicnucleus seygenerally weaker `than 'theqsum of the individual lected fromthe group consisting of heterocyclic effects produced by ,eosin dyes{acidi} and the 1.3 nuclei of the benzothiazole series, heterocycliccyanine `dyes (basic). nuclei of the a-naphthothiazole series, hetero-"We have novv found that certain acid carbocyclic nuclei of the2quinoline series and heterocyanine dyes, e. g. acid 'thiacarbocyani-ne,acid cyclic nuclei of the 4-quinoline series, except thatthia2'carbocyanine, ,acid 4'carloocyanine, acid Zrdoesnot representthenon-metallicfatoms necloenzothiacarbocyanine and acid benzothia-2- zoessary to complete a ,heterocyclic .nucleusof the oarbocyanine dyes, canbe supersens'i-tized 'with -quinoline series when Z represelfi'ts thenonstylylbases, providing the acid dyes lcon-tain spemetallic atomsnecessary to .complete a 1heterocic acid groups, i. e. carboxyethyland/or sul-focyclic nucleus .of the a-naphthothiazole series. ethylgroups on at least one of the auxoclnomo- More specically Z representsthe .non-metallic iihoricnitrogen aOmS- Theacid dyes Containing :.3atoms necessary to .complete a lheterocyclic nucarboxymethyl groups onthe auxochromopilcric cleus, such Aas benzothiazole,Li-methylbenzothinitrogen atoms are not supersensitized lay the azole,.5-methylbenzothiazoleJ -6rmethylbenzothi styryl bases, nor rare Iacidoxaand selenecarboazole, 4-ch1orobenzothiazole, -chlorobenzothicyaninedyes. azole, 6chlorobenzothiazole, rl-chloroloenzothi- It '-is,accordingly, Van object of our invention y) azole, -bromobenzothiazolaI'6-bromoleenzothi to provide photograph-ic emulsions sensitized withazole, -iodobenzothiazole, -iodobenzothiazole, supersensitizi-ngcombinations of acidcarbocyfvihenylbenzothiazole,.,fphenylbenzothiazole, 4-

anine dyes and styryl bases. A further object is methoxybenzothiazoleoernethoxybenzothiazole, toprovide a process 'for-the #preparation ofsuch 6-methoxybenzothiazoley 5,6-dimethoxybenzothinovel emulsions.lStill other obiectsW-i'll fbecome azole, 5-ethoXybenzothiazo1e,5,6-dioXymethylene- 'apparent-'hereinafter benzothiazole,a-naphthothiazole, S-Jnethoxy-a- `The acid carbocyanine dyes which Weemploy naphthothiazole, '7-methcxy-a-naphthothiazole, Ain practicing our'invention can 'be represen-ted etc. More specifically Z1 represents thenon- "by the following-generalformulasz y metallic atoms necessary tocomplete a benzothi- I ,Z\ B v A,Zie

wherein D represents a member .selected from azole or ana-naphthothiazole nucleus such -as the 4group vconsisting `of -acarboxyl group .and a those set forth above `under lZ l-or `a2-qu1-nol1ne suifo .'gronp, vn represents a positive integer :ofnucleus, e. g. 2-quino1ine, B-methoxyZ-quinoline,

(a) Anhydro 5,5-dich1oro 9 ethyl-3,3'di

sulfoethylthiacarbocyanine hydroxide having the formula:

thiacarbocyanine hydroxide. (f) Anhydro-3,3' di carboxyethyl-9-ethy1-thiacarbocyanine hydroxide. Anhydro 3,3 di--carboxyethyl-5,5'dichloro-9-methylthiacarbocyanine hydroxide.Anhydro-3,3'-di-,B-carboxyethyl 9 ethyl- 5,5'-diphenylthiacarbocyaninehydroxide. Anhydro 3,3'-di-'-carboxyethyl-9-methy1-6,7,6,7'-dibenzothiacarbocyanine hydroxide.

Typical of the dyes represented by Formula II above are:

formula:

s l \C-cH=oH-CH zHu 1 These dyes are ordinarily obtained as their semihydroiodides.

4 Typical of the dyes represented by Formula III above are:

(o) 3--carboxyethyl 3,9 diethyl-5,5dichlo rothiacarbocyanine iodidehaving the forthia-2carbocyanine iodide.

The styryl bases which we employ are heterocyclic nitrogen basescontaining a dialkylaminostyryl group in a reactive position, i. e. inthe aor 'y-position. These bases can be represented by the followinggeneral formula:

Y R3 wherein e represents a positive integer of from 1 to 2, D1represents a p-arylene group of the benzene series, e. g. phenylene,methoxy-p-phenylene, etc., R2 and R3 each represents yan alkyl groupwhich can be the same or different, e. g. methyl, ethyl, n-propyl,n-butyl, isobutyl, -hydroxyethyl, -methoxyethyl, etc., and Z2 representsthe non-metallic atoms necessary to complete a heterocyclic nucleuscontaining from 5 to 6 atoms in the heterocyclic ring, e. g. aheterocyclic nucleus of the thiazole series (e. g. thiazole,4-methylthiazole, 4-phenylthiazole, 5methylthi azole, -phenylthiazole,4,5-dimethylthiazole, 4,5- diphenylthiazole, 4-(2-thienyl) thi-azole,etc), a heterocyclic nucleus of the benzothiazole series (e. g.benzothiazole, 4-chlorobenzothiazole, 5- chlorobenzothiazole,6chlorobenzothiazole, 7- chlorobenzothiazole, 4-methylbenzothiazole, 5-methylbenzothiazole, G-methylbenzothiazole, 5- bromobenzothiazole,-broinobenzothiazole, 4- phenylbenzothiazole, 5-phenylbenzothiazole, 4-methoxybenzothiazole, -methoxybenzothiazole, G-methoxybenzothiazole,-iodobenzothiazole, 5- iodobenzothiazole, 4-ethoxybenzothiazole,5-ethoxybenzothi-azole, 5,6-dimethoxybenzothiazole,5,6-dioxymethylenebenzothiazole, 5-hydroxybenzothiazole,G-hydroxybenzothiazole, etc), a heterocyclic nucleus of thenaphthothiazole series (e. g. a-naphthothiazole, -naphthothiazole, 7-methoxy-a-naphthothiazole, 8-methoxy-a-naphthothiazole,5-methoxy--naphthothiazole, 5- ethoxy--naphthothiazole, etc.), aheterocyclic nucleus of the selenazole series (e. g. 4-methylselenazole,4-phenylselenazole, etc.), a heterocyclic nucleus of the benzoselenazoleseries (e. g. benzoselenazole, -chlorobenzoselenazole,6-methoxybenzoselenazole, 5-methoxybenzoselenazole,

etc), a heterocyclic nucleus of the naphthoselenazole series (e. g.a-naphthoselenazole, -naphthoselenazole, cet), a heterocyclic nucleus ofthe oxazole series (e. g. 4-methyloxazole, 4-phenyloxazole,-methyloxazole, 4,5-diphenyloxazole, 4- ethyloxazole, 5phenyloxazole,4,5-dimethyloxazole, eta), a heterocyclic nucleus of the benzoxazoleseries (e. g. benzoxazole, -hydroxybenzoxasole, vii-hydroxybenzoxamle,-5-chlorobenzoxazole, S-methoxgybenzoxazole, -z-methoxybenzoxazole, 5-bromobenzoxazole, Ietc.)., o, iheterocyclic.nucleus of the naphthoxazoleseries (e. ig. fa-naphthoxazole, -.naphthoxazola etc, :a .fheterocyclic.nucleus :of ,the Z-quinoline series l(erg. 2-quino1ine,S-ntsethyl-Z-quino1ine, -7-methyl-,2-quinoline, -8- methyl-Z-quinoline,-chloro-Z-quinoline, 8chlo ro-2-quinoline, V.4.-ohloro -2-quinoline,5-ethoxy--2- lquinolin'e, 4v-etho'xy 2-quinoline, ,.'I-ethoxy-2-qunoline, 6-hydroxy-2-quinoline, Z-hydrox-yeZ- 4qninoline,=f6-methoxy-jz-quinoline, etc.) ,ra heterocyclc :nucleus v of the 4-quino1ine :series(e. '4- fquinoline, G-methoxy-i-quinoline, 7-m'ethyl-4- quinoline,8-methy1-4-quinoline, etc, .fa :heterocyclic rnucleus of the Z-pyridineseries (e.'g."2-'pyridine, r-chloro-Z-pyridine, ietc), @a heterocyclicnucleus of .the yi-pyridine series V(e. lg. 4-pyridine,-chloro--pyridine, etc.)., ja .heterocyclic :nucleus of .the,isoquinoline series (e. zg. iso'quinoline, etc.)

etc.

' Typical -of the styryl bases represented `by r'FormulaIV above are:

`(l) 4'2l-p-dietnylaminostyrylbenzothiazole N (2)`12pdiethylamnostyryl--naphthothiazole. (3)vZ-p-diethylaminostyrylpyridine. i4)"2-p-diethylaminostyrylbenzoselenazole. t5)i2-p-diethylaminostyrylquinoline (6) 4-pdiethylaminostyrylquinolneNQ-CHL-CH-Qmoznm (7) 2-p-diethylaminostyryl-4-methylthiazole chloride,-chlorobromide, -chlorobromoiodide, -iodochlorida -bromide andveloping-out emulsions. These ordinarily employed silver halidedeveloping-out emulsioi'is'are emulsions which form surface latent image(see British Patent 581,772, accepted October 24, 1946). However, silverhalide emulsions which form latent image mostly inside the silver halidegrains (see British Patent 581,772, supra) can also be employed.

ordinarily employed gelatino-silver-haiide developing-out emulsions, e.g. gelatino-silver- -bromoiodide del in the emulsion.

The acid carbocyanine adyes and the `styryl bases fcan be employed invarious concentrations depending uimonthe effects desired. Inpreparingour supersensitized emulsions, we have found that for the 4ordinaryygeiatino-silver-halide emulsions theV 'concentration of the individualacid carbocyanine dyes is advantageously within the range, '9;03 to'0.2g. per mole of silver halide in the emulsion, and that theconcentration of the fstyryl base is advantageously withinthe ran-ge,@i603 to 40.05 g. per :mole of silver Yhalide `in the emulsion.

it is, ofcourse, well knownzin the art that Lthe sensitivity conferredupon 4an emulsion lby 2a sensitizing zdye (or dyes) .does not increaseproportionately :to the Aconcentration of the Adye (or dyes) in Vtheemulsion, but passes through a maxi-mum as the vconcentration isincreased. Likewise, the sensitivityY conferred 'on emulsions by our newISupersensitizing combinations passes through a .maximum vas thelconcentration iis increased. In determining the `optimum concentrationrfor any of our ynew supersensitizing "cominitiations it is advisable tobegin with a :supersensl'lizing combination in which the sensitizin'gdye is at somewhat `less than `its optimum lconcentration, since '.theoptimum concentration of 'the :.sensitizing ydye 'alone `does not.necessarily correspond to lits optimum concentration `in thesupersensitising combination..

The optimum concentration `of a sensitizing dye (i. e. the concentrationat which the greatest sensitivity is conferred on the emulsion) can bereadily determined in a manner well known to ythose skilled in the artby measuring the sensitivity of a series of emulsion coatings (of the.same emulsion) containing dii-ferent concentrations of the sensitizingdye. The optimum concentration of any of our new supersensitizingcombinations can, of course, be determined simi- Early, 4by measuringthe sensitivity of `a 'series of emulsion coatings containing differentconcentrations of the Vsensitizing dye in combination with a styrylbase.

The acid carbocyanine dyes are advantageously added to the emulsions byrst forming a Watersoluble salt of the racid carbocyanine dye anddissolving the water-soluble salt in water, methanol or ethanol, or amixture of Water, and methanol or ethanol, and dispersing the resultingsolution The salts are advantageously formed by adding the acidcarbocyanine dye wet with a little water, methanol, or ethanol to analkali metal hydroxide, e. g. sodium or potassium hydroxide, or ammoniumhydroxide, or an amine, e. g. methylamine, ethylamine, dimethylamine,diethylamine, trimethylamine, triethylaminafethanolamine,diethanolamine, trietrh'anolamine, pyridine, l\lmethylpiperidine,n-propylamine., isopropyla-mine, n-butylamine, ,B-ethcxyethylamine, etc.Yand taking up the salt Vwhich -f'orzns in a suitable solvent, eg.water, methanol, ethanol or a mixture of water and methanol, Aa mixtureof water and ethanol, etc.v The `acid carbocyanine dyes can also 'beadded to the emulsions in the free acid forms in solution in anap-.propriate solvent, e. g. methanol.

The styryl'bases can be added 'to the emulsions .from their solutions inappropriate solvents, e. 1g. methanol. The styryl bases and the vacidcarbocyanine can be added to the emulsion separately or simultaneously..Both 'should be uniformly distributed throughout the emulsion.

The amount of acid carbocyanine dye and :styryl ybaseiactuallyincorporated in theemuls'on will, of course, vary from dye to dye andstyryl base to styryl base, according to the emulsion employed andaccording to the eiect desired. The regulation and adoption of the mosteconomical and useful proportions will be apparent to those Theaccompanying drawing illustrates the supersensitizing eiiect obtainedwith three fof our new 'combinations in gelatine-silVer-bromoiodideemulsions. Each figure of the drawing is a dia'- grarnmatic reproductionof two spectrograms. yIn

skilled inthe art upon making the ordinary obeach figure, thesens1t1v1ty of the emulsion conservations and tests customarily employedin the taining only the acid sensitizing 'dye is repreart.v Ourinvention is directed to any emulsion sented 4by the broken-line curve,while the'sensicontaining a combination of the acid carbotivity of thesame emulsion containing the sensicyanine dyes and styryl bases wherebya Superm tizin'g dye in combination with a styryl base' is sensitizingeffect is obtained. The supersensirepresented by the solidV line curve.Inasmuch tized emulsions can be coated on a suitable supas the styrylbases have little or no sensitizing port, e. g. glass, cellulose esterlm, polyvinyl aceelect on gelatino-silver-bromoiodide emulsions,talresin film, paper, etc., to a suitable thickness no spectrogram forthe emulsion containing the and dried. The details of such coatingmethods i5 styryl base is shown. j are well known to those skilled inthe art. In'Fig. 1, curve A represents the sensitivity of The followingexamples will serve to illustrate a gelatino-silver--bromoiodideemulsion containfurther the manner of practicing our invention. inganhydro-5,5'-dichloro 9-ethyl-3,3f-di--sul- To different portions of thesame batch of photofoethylthiacarbocyanine hydroxide (ina concengraphicgelatine-silver-bromoiodide emulsion g.; tration of 85 mg. per mole ofsilver halide) and were added (l) a'styryl base, (2) an acid carbocurveB represents the sensitivity of the same cyanine dye and (3) acombination of the basic gelatino-silverabromoiodide emulsion containingdye and the acid carbocyanine dye. The diieranhydro 5,5- dichloro 9ethyl 3,3 di ent portions'of emulsion were then coated on glasssulfoethylthiacarbocyanine hydroxide (in a consupports and exposed inthe usual manner in a 2.7 centration of 85 mg. per mole of silverhalide) spectrograph and in a sensitometer Vto white plus2-(p-diethylaminostyryl)benzothiazole in a iight and through lters,including a Wratten concentration of 8.5 mg. per mole of silver halide.No. (red) filter and a Wratten No. 12 (minus In Fig. 2, curve Crepresents the sensitivity of a blue) lter. Following are severalexamples of gelatino-silver-bromoiodide emulsion containing suchemulsions together with the speed (clear 3 carboxyethyl 1 ethylthia 2-carbocyor white light, red and minus blue), the gamma anine iodide (in aconcentration of 85 mg. per and the fog obtained. The speed number givenmole of silver halide) and curve D represents the in these examples is10 /i where z' is the inertia in sensitivity of the sameygelatino-silver-bromometer candle seconds of sunlight quality. iodideemulsion containing B--carboxyethyl-li Y Tablel I Clear Wratten No. 25Wratten N o. 12

(red) lter (minus blue) filter Dyc Speedl Gamma Speed Gamma Speed GammaFog vAnhydro-,5dichloro9ethyl-3,3'-di--sulioethylthiacarbocyaninchydr5nde(1),.0s5 g./m5i. s1iverh511de 410 3.10 66 2. 96 100 3.24 .o5 I,.085 g./mol.i2(p-dicthylaminostyryl) be g./m61. siiverhaiide-.- 510 3.1613s 2.84 265 2. s0 .0s I, .085 g./m0l.|2(pdie g./mol. silver halide 5502. 9.4 118 3.48 A 210 3.20 .06 I,..085.g./mol.i2(pdiethyl halide 49o3.54 105 3.14 175 3.40 .07 Iy .085 g./mol.|2(pdiethyla .0085 g./mo1.silver halide 2 420 3.30 56 3.40 120 3. 18 ,062(pdiethylaminostyryDbenzothiazole ethiod haude 360 3.36 5.9 0. 68 16 2.96 .o5

Table II Wratten No. l2 Clear (minus blue) filter Dyes Speed1 GammaSpeed Gamma Fog Anhydro-S, 3-di-B-carboxyethylthiacarbocyanine hydroxide(III), .085 g./mol. silver halide 210 1.70 1.47 .09 III, .085g./mo1.+2(pd1ethylaminostyryl)benzothiazole (Il), .0085 g./mol. silverhalide.A 280 1. 41 92 1.47 .26 Anhydro,3di--carboXyethyl-Q-methylthiacarbocyanine hydroxide (IV), .085

gjmol. silver halide ...v 255 l. 65 61 1. 40 11 IV, .085g./mol.+2(pdiethylaminostyryl)benzothiazole (II), .0085 gJmol. silverhalide 295 1.44 102 1.60 .21 Anhydro-S, 3dicarboxyethyl5,5dich1oro-9methylthiacarbocyanine hydroxide (V), .085 g./mol. silverhalide 130 1.49 112 1.04 .07 V, .085g./mcl.+2(p-diethylamnostyryl)benzothiazole (Il), .0085 gJmol. silverha1ide 138 1.60 271 1.48 .10 Anhydro-S--carboxyethy1-5,5-dichloro9methyl3sulfoethylthia-carbocyanine hydroxide (VI), .085g./mol. silver halide 410 2.70 148 2.62 .04 VI, .085g./mol.|2(p-diethylaminostyryl)benzothiazole (II), .0085 g./mol. silverhalide. 610 2.72 230 2.94 .05Anhydro--chloro-l-ethyl-8--sulfoetliylthia-2'carbocyanine hydroxide,(VII), .085v

g./m0l. silver halide.: .L 380 2. 76 39 3. 56 .04 VII, .085g./ruol.+2(pd1ethylaminostyryl)benzothiazole (II), .0085 gJmol. silverhalide. 360 3.10 55 3. 28 .04 3-5-Carboxyethyl-lethylth1a2'carb0cyanineiodide (VIII), .085 g./mo1. silver halide 440 2. 78 145 3. 24 .05(VIII), .O g./mol.+2(p-diethylaminostyryl)benzothiazolc (II), .0085g./mol.silver halide. 560 8. 10 265 3. 04 O6M]-(gfboxyethyl-lethyl9methylthia2carbocyaninc iodide (IX), .O85 g./mol.silver 410 2. 50 165 2.44 .04

B. l e IX, .085`g./mol.+2(pdiethylaminostyryl) benzothiazole (II), .0085g./m0l. silver halide 450 2.84 220 2.84 .04Anhydro---'carboxyethyl-5-chlorothia-2carb0cyanine hydroxide, semihydroiodide,

(X), .085 gJmol. silver halide 295 2. 58 71 3. 22 .05 X, .085g./mol.+2(p-diethylaminostyryl(benzothiazole (II), .0085 g./m0l. silverhalide 420V` 2. 76 148 3.02 .05

lia 2 These data demonstrate that the effect obtained by using inferiorto that obtained with the styryl base.

la styryl dye instead of the corresponding styryl base is markedly 9ethylthia2carbocyanine iodide (in a concentration of 85 mg. per mole ofsilver halide) plus Z-(p-diethylaminostyryl)benzothiazole in aconcentration of 8.5 mg. per mole of silver halide.

In Fig. 3, curve E represents the sensitivity of agelatino-silver-bromoiodide emulsion containinganhydro3,3'di--carboxyethylthiacarbocyanine hydroxide (in aconcentration of 85 mg. per mole of silver halide) and curve Frepresents the sensitivity of the same gelatino-silver-brornoiodideemulsion containing anhydro-3,3dicar boxyethylthiacarbocya-ninehydroxide (in a concentration of 85 mg. per mole of silver` halide) plus2-(p-diethylaminostyryl)benzothiazol'e in a concentration of 8-.5 mg.per mole of' silver halide.

Thelacid carbocyanine dyes defined by Formula I, wherein D represents acarboxyl group and- Q- representsa --COOr group, can be preparedy asdescribed in United-StatesfPatent 2,231,658, dated February ll, 1941;For example, a 2`methyl= benzothiazole carboxyethobromide canbe Ycondensed with ethyl orthoformate, ethyl orthoacetate or ethylorthopropionate, in pyridine, to give anhydro 3,3-dicarboxyethylthiacarbocya.-

nine hydroxide, anhydro-S-,S-di-warboxyethylg'emethylthia'carbocyaninehydroxide or anhydro- 2"'-methyl-a-naphthothiazple 'carboxyethobromidecan be similarly condensed with the aforesaid ortho esters.

The acid carbocyanine dyes deiinedby'l'ormula I, wherein D represents asulfo group and'Q- represents a -SOzQ- group, can be prepared as de.-scribed in the copending application ofv Robert Sprague, Serial No'.736,405, filed March 2l, 1947:, now U. S. Patent 2,503,776, dated4 AprilIl, 11950. ForV example, a Z-methylbenzothiazole -sulfoethobromide canbe condensed'vvith ethyl ortho'- formate, ethyl orthoacetate' or ethylorthopropionate, in pyridine, to give anhydro'3;3"-di--sulfoethylthiacarbocyanine hydroxide', anhydro-9-methyl-3,3-di--sulfoethylthi'acarbocyanine hydroxide oranhydro-9ethyl3,3"-di--sulfoethyllthiacarbocyanine hydroxide.2methylanaph thothiazole -sulfoethobromide can be similarly condensedwithV the aforesaid ortho esters.

The vacidy carbocyanine dyesdenedI by Formula I', wherein D represents acarboxyl group and Q represents a -SOzO- group can be prepared" asdescribed inthe copending application; of vRobert H. Sprague, Serial No.71.36.3405', supra. Forexample, the addition product of3-,B-carboxyethyl-5- chloro-2thioacetylmethylenebenzothiazoline. andmethyl-p-toluenesulfonate can be condensedwith chloro- 2methylbenzothiazole sulfo- 'ethobromide in pyridine, to give'anhydro-Bc-- carboxyethyl- 5,5 dichloro--Q methyl- 3sulfoethylthiacarbocyanine bromide. Anhydro- 3'- carboxyethyl- 3sulfoethylthiacarbocyanine bromide can be prepared by condensing2acetanilidovinylbenzothiazole^ecarboxyethobromide withZ-methylbenzothiazole I-sulioethobromide, in ethyl alcohol containingtriethylamine. i

The acid carbocyanine dyes defined by Formula II wherein R represents ahydrogen atom, can be prepared-as described by Robert H'. Sprague in hiscopending application Serial No. 736,405, supra. For example,Z--acetanilidoquinoline alkiodides, 4--anilinoquinoline alkiodides,2acetanilido benzothiazole alkiodides andZ--acetanilidovinyl-a-naphthothiazole alkiodides can be condensed, inethyl alcohol'contaning-.triethylamine,.

with 2-methylbenzothiazole ,B-sulfoethobromide,Z-metbyl-uenaphthothiazole -sulfoethobromide l0 and2-methylIS-naphthothiazole -sul'foethobromide to giveanhydro-1'alkyl3sulfoethyl; thia2carbocyanine hydroxides, anhydro-1'alkyl-B--sulfoethylthia-Z-carbocyanine hydroxides,anhydro-S-alkyl-S--sulfoethylthiacarbocyanine hydroxides, etc.

The acid caribocyanine dyes defined by Formula II wherein R representsan alkyl group, can be prepared by condensing acyclammonium quaternarySalt selected from those representedv by the following general formula:

wherein R, X and Z have the values given above and R2 represents analkyl group, e. g. methyl, ethyl, n-propyl, isobutyl, n-butyl, etc.,with a cyclammonium quaternary salt selected from those represented Ibythe following general forfmula:

wherein n, R1, X, and Z1 have-the values given above in the presenceof'a tertiary airline such as triethlamine, in ethyl` alcohol. See thecepending application of` Robert I-I.- Sprague, supra.

The acid carbocyanine dyesv represen-ted. by Formula II above wherein R:represents` a, hy.- drogen atom can be prepared as described in UnitedStates Patent 2,231,658, dated February 11 wel. For exampleZ-methylbenzothiazole fcarboxyethiodide can be condensed' with 2r--acetanilidovinylquinoline ethiodide or 4 ,8J- anilinovinyllepidineethiodide in the presence of triethylamine, in ethyl alcohol. Frequentlythese dyes are obtained as heini hydroiodides which can be representedas illustrated below for anhydro-3- carboxyethyl-lethyl-G,'7benzothia2carbocyanine hydroxide, viz.

The acid carbocyanine dyes which are represented by Formula 1H wherein Rrepresents' alkyl can be prepared vby condensingthe addition product ofaS--carboxyethyl-Z-thioacylmethylenebenzothiazolinewith an alkyl salt orthe addition product of a 3carboxyethyl2thieacylmethylene-anaphthothiazoline with an alkyl salt, with a quinaldine, alepidine, a Z-methylbenzothiazole or a 2-methyl-a-naphthothiazolequaternary salt, in the presence of triethylamine in ethyl alcohol. Thefollowing examples will il- I 114 g. (1 mol.) of 3--carboxyethyl-Z-thio-`acetylmetl'lylenebenzothiazoline and 0.93 g. (1

mol.) of methyl p-toluenesulfonate were heated together at thetemperature of the steam-bath for 30 minutes. To the resulting productwas added 1.5 g. (1 mol.) of quinaldine ethiodide, 25 cc. of absoluteethyl alcohol and 0.5 g. (1 mol.) of triethylamine. The reaction mixturewas .heated at the reiluxing temperature for minutes. After cooling, themixture was treated with 5 cc. of acetic acid and the Whole chilled. Thedye was collected on a lter and Washed first with acetone and thenwater. The yield of dye was 44% crude and 26% after tworecrystallizations from methyl alcohol. The dull green crystalshadmelting point 167-169 C. with decomposition.

l CHz-CHz-C 0 OH 1.1 g. (1 mol.) of 3carboxyethyl5-chloro-2-thiopropionylmethylenebenzothiazoline and 0.62 g. (l mol.) of methylp-toluenesulfonate were heated together at the temperature of thesteambath for 30 minutes. To the resulting product was added 1.0 g. (1mol.) of quinaldine ethiodide, cc. of absolute ethyl alcohol and 0.33 g.(l mol.) of triethylamine. The reaction mixture VWas heated at thereluxing temperature for minutes. After cooling, the mixture was treatedwith an excess of acetic acid and the whole chilled. The dye wascollected on a iilter and Washed iirst with acetone and then Water. Theyield of dye Was 30% crude and 15% after two recrystallizations frommethyl alcohol. The bronze crystals had melting point 212-214 C. withdecomposition.

Esccbmple 0.--3 caboxyethyl 5,5-cz'chioro- 3,9-diethylthiacarbocyanineiodide CHe-CHz--COOH 2.83 g. (1 mol.) of5-chloro-3-ethyl-2-thiopropionylmethylenebenzothiazoline and 1.86 g. (1mol.) of methyl p-toluenesulfonate were heated together' at thetemperature of the steambath for 30 minutes. To the resulting product,was added 3.5 g. (1 mol.) of 5-chloro-2-methylbenzothiazole-carboxyethiodide, 25 cc. of absol Y D-cHr-oHland lute ethyl alcoholvand 1.0 g. (1 mol.) of triethy'lamine. The reaction mixture Washeatedat the refluxing temperature for 30 minutes. After cooling, the mixturewas treated With an excess of acetic acid and the whole chilled. The dyewas collected on a lter and washed rst with acetone and then water. Theyield of dye was 35% crude and 19% after two recrystallizations frommethyl alcohol. The dark green crystals had melting point 254-255" C.,with decomposition.

The 3 -carboxyethyl-2-thioacetylmethylene-V benzothiazoline and3--carboxyethyl--chloro- 2 thiopropionylmethylenebenzothiazolineemployed in the foregoing Examples A and B can be prepared by condensingZ-methylbenzothiazole- -carboxyethyl ethiodide With methyldithioace--tate or by condensing 5-chloro-2-methylbenzothiazole -carboxyethiodidewith methyl dithiopropionate, in the presence of triethylamine inpyridine as described in the copending application of Robert H. Sprague,Serial No. 730,564, filed February 24, 1947, now U. S. Patent 2,481,698,dated September 13, 1948. 5-ch1oro-3-ethyl-2-thiopropionylmethylenebenzothiazoline is described in United StatesPatent 2,369,646, dated February 20, 1945.

Anhydro 3,3'di carboxyethyl 9 ethyl- 5,5-diphenylthiacarbocyaninehydroxide can be prepared by condensing 2-methy1-5-phenylbenzothiazole-carboxyethiodide with ethyl orthopropionate in pyridine, in the manner`described by Gertrude Van Zandt and Leslie G. S. Brooker in theircopending application Serial No. 711,816, filed November 22, 1946, nowU. S. Patent 2,515,913, dated July '18, 1950.

The benzothiazole, a-naphthothiazole and quinoline nuclei involved inthe acid carbocyanine dyes employed in practicing our invention cancarry substituents, such as methyl, ethyl, methoxyl, ethoxyl, phenyl,hydroxyl groups and chlorine, bromine or iodine atoms, for example.Similarly the benzothiazole, naphthothiazole, benzoxazole,naphthoxazole, benzoselenazole naphthoselenazole, quinoline, pyridine,simple thiazole, simple oxazole, simple selenazole, etc. nuclei involvedin the styryl bases can carry substituents, e. g. those set forth abovein connection with the acid dyes.

Hydroxycyclammonium quaternary salts and cyanine dyes made therefrom aredescribed by E. Van Lare and L. G. S. Brooker in their copendingapplication Serial No. 18,846, filed April 3,1948.

What we claim as our invention and desire to be secured by LettersPatent of the United States is:

1. A photographic silver halide emulsion sensi- Ytized with asupersensitizing combination of at least one sensitizing acid.carbocyanine Vdye selected from the group consisting of thoserepresented by the following three general formulas:

and

wherein D represents a member selected from the group consisting of acarboxyl group and a sulfo group, n represents a positive integer offrom 1 to 2, Q- represents a member selected from the group consistingofV -COO- and -SO2O, R represents a member selected from the groupconsisting. of a hydrogen atom, a methyl group and an ethyl group, R1represents a primary alkyl group of the formula Cdl-12am whereindvrepresents a positive integer of from 1 to 4, X represents an anion, Zrepresents the non-metallic atoms necessary to complete a heterocyclicnucleus selected, from, the group consisting of heterocyclic nuclei ofthe benzothiazole series and heterocyclic nuclei of thea-cnaphthothiazole series, and Z1 represents the nonfmetallic atomsnecessary to complete a heterocyclic nucleus selectedv from the group.consisting of heterocyclic nuclei of the benzothiazole series,heterocyclic nuclei of the a-naphthothiazole series, hetero,- cyclicnuclei o the2quinoline series and. heterocyclic nuclei of the4-quinoline series, except that Z1 does not represent the non-metallicatoms necessary to complete a heterocyclic nucleus of the 4-quinolineseries when Z represents the nonmetallic atoms necessary torpomplete aheterocyclic nucleus of the a-naphthotniazole series, together with atleast one styryl base.

2. A photographic emulsion as defined inv claim 1 wherein thephotographic emulsion is a gelatino-silver-halide developing-outemulsion.

3.- A photographic emulsion as dened inclaim 1, wherein the photographicemulsion is a gelatino-silverehalide developing-out emulsion and thestyryl base is selected from the group of styryl bases represented bythe followingA genera-1 formular thiazole series, heterocyclic nuclei ofthe benzothiazole series, heterocyclic nuclei of the naphthothiazoleseries, heterocyclic nuclei of the selenazolevseries, heterocyclicnuclei of the benzoselenazole series, heterocyclic nuclei of thenaphthoselenazole series, heterocyclic nucleiV of the oxazole series,heterocyclic nuclei of the benzoxazole series, heterocyclic nuclei ofthe naphthoxazole series, heterocyclic nuclei of the quinoline series,heterocyclic nuclei of the pyridine series and 'heterocyclic nuclei oftheisoquinoline series.

glgA gelatino-silverehalide emulsion sensitized with a supersensitizingcombination of atleast one sensitizing acid carbocyanine dye selectedfrom the groupconsvisting of those represented by the following, generalformula:

14 Rv represents a member selected from the. 'group consisting of ahydrogen atom, a methyl-group and an ethyl group, Zy represents thenon-metallic atoms necessary to complete a heterocyclic nucleus selectedfrom the group consisting' of heterocyclic nucleiV of the benzothiazoleseries and heterocyclic nuclei of thea-naphthothiazole series, and Z1represents the non-metallicatoms necessary to complete a heterocyclicnucleus selected from the group consisting of heterocyclic nuclei of thebenzothiazole series, heterocyclic nuclei of the a-naphthothiazoleseries, heterocyclic nuclei of the 2-quinoline series and heterocyclicnuclei of the 4-quinoline series, except that Z1 does not represent thenon-metallic atoms necessary to complete a heterocycliclnucleus of thefl-quinoline series when Z represents the non-metallic atoms necessaryto complete a heterocyclic nucleus,l of the a-.naphthothiazole series,together with a styryl base.

5. A photographic emulsion as deiined in claim 4, wherein the styrylbase is selected from the group of styryl bases represented by thefollow ing general formula:

wherein e represents a positive integer of` from Y1. to. 2, D1represents a p-arylene group of the benzeneseries, R2 and R3 eachrepresents a primaryl alkyl group of the formula C'dHzaJfi Whereind'represents a positive integer of from 1 to.4, and Z2 represents thenon-metallic atomsvv` necessaryl to ,complete a heterocyclic nucleus.:se'- lected fromr the group consisting` of heterocyclic nuclei of thethiazole series, heterocyclic nuclei of the benzothiazole series,heterocyclic nuclei of the naphthothiazole series, heterocyclic. nucleiof the selenazole series, heterocyclic nuclei of the benzoselenazoleseries, heterocyclic nuclei of the naphthoselenazole series,heterocyclic `nuclei of the oxazole series,r heterocyclic Vnuclei of thehenzoxazole series, heterocyclic nuclei4 of the naphthoxazole series,heterocyclic nuclei of the quinoline series, heterocyclic nuclei of thepyridine series and heterocyclic nucleiA of the isoquinoline series.

6. A photographic silver halide emulsion sensitized with asupersensitizing` combination of a sensitizing acid carbocyanine dyeselected from the group consisting of those represented by the followinggeneral formula:

//Z\\ R ,Z1` -osorCHi-CHQ-Nc-cree-oicn=cn iI-R, wherein 11, represents apositive integer of from i to 2, R represents a member selected from thegroup consisting of a hydrogen atom, a methyl group andan ethyl group,`R1 represents a primary alkyl group of the formula CaHzdJfi Wherein drepresents a positive integer of from 1 to 4, Z represents thenon-metallic atoms necessary to complete aheterocyclic nucleusselectedfrom the group consisting of heterocyclic nuclei, of

the group consisting of a carboxyl group and a sulfo group, n representsa positive integer of from 1 to 2, Q- represents 'a memberselected fromthe group consisting of COO- and 'wherein D represents a member selectedfrom 70 the benzothiazole series and heterocyclic nuclei of thea-naphthothiazole series, and Z1 represents the non-metallic atomsnecessary, to complete a heterocyclic nucleus selected from the groupconsisting or heterocyclic n'uclei ofthe benzothiazole series,heterocyclic nucleici .the afnaphthothia zole, heterocyclic nuclei ofthe 2-quinoline series and heterocyclic nuclei of the 4-quinolineseries, except that Z1 does not represent the non-metallic atomsnecessary to complete a heterocyclic nucleus of the 4-quinoline series,when Z represents the non-metallic atoms necessary to complete aheterocyclic nucleus of the a-naphthothiazole series, together with atleast one styryl base.

, 7. A photographic emulsion as defined in claim 6, wherein the styrylbase is selected from the group of styryl bases represented by thefollowing general formula:

wherein e represents a positive integer of from l to 2, D1 represents ap-arylene group of the benzene series, R2 and R3 each represents aprimary alkyl group of the formula CaH2a+1 wherein d represents apositive integer of from 1 to 4, and Z2 represents the non-metallicatoms necessary to complete a heterocyclic nucleus selected from thegroup consisting of heterocyclic nuclei of the thiazole series,heterocyclic nuclei of the benzothiazole series, heterocyclic nuclei ofthe naphthothiazole series, heterocyclic nuclei of the selenazoleseries, heterocyclic nuclei of the benzoselenazole series, heterocyclicnuclei of the naphthoselenazole series, heterocyclic nuclei of theoxazole series, heterocyclic nuclei of the benzoxazole series,heterocyclic nuclei of the naphthoxazole series, heterocyclic nuclei ofthe quinoline series, heterocyclic nuclei of the pyridine series andheterocyclic nuclei of the isoquinoline series.

8. A photographic gelatino-silver-halide developing-out emulsionsensitized with a supersenstizing combination of at least onesensitizing acid carbocyanine dye selected from the group consisting ofthose represented by the following general formula:

wherein n represents a positive integer of from 1 to 2, R represents amember selected from the lgroup consisting of a hydrogen atom, a methylgroup and an ethyl group, R1 represents a primary alkyl group of theformula CdH2d+1 Wherein d represents a positive integer of from 1 to 4,X represents an anion, Z represents the nonmetallic atoms necessary tocomplete a heterocyclic nucleus selected from the group consisting ofheterocyclic nuclei of the benzothiazole series and heterocyclic nucleiof the a-naphthothiazole series, and Z1 represents the non-metallicatoms necessary to complete a heterocyclic nucleus selected from thegroup consisting of heterocyclic nuclei of the benzothiazole series,heterocyclic nuclei of the a-naphthothiazole series, heterocyclic nucleiof the 2-quinoline series and heterocyclic nuclei of the 4-quinolineseries, except that Z1 does not represent the non-metallic atomsnecessary to complete a heterocyclic nucleus of the a-naphthothiazoleseries, together with at least one styryl base.

9. A photographic emulsion as dened in claim 8, wherein the styryl baseis selected from the group ofjstyryl bases represented by thefollowgeneral formula:

wherein e represents a positive integer of from 1 to 2, D1 represents ap-arylene group of the benzene series, R2 and R3 each represents aprimary alkyl group of the formula CdH2d+1 wherein d represents apositive integer of from 1 to 4, and Z2 represents the non-metallicatoms necessary to complete a heterocyclic nucleus selected from thegroup consisting of heterocyclic nuclei of the thiazole series,heterocyclic nuclei of the benzothiazole series, heterocyclic nuclei ofthe naphthothiazole series, heterocyclic nuclei of the selenazoleseries, heterocyclic nuclei of the benzoselenazole series, heterocyclicnuclei of the naphthoselenazole series, heterocyclic nuclei of theoxazole series, heterocyclic nuclei of the benzoxazole series,heterocyclic nuclei of the naphthoxazole series, heterocyclic nuclei ofthe quinoline series, heterocyclic nuclei of the pyridine series andheterocyclic nuclei of the isoquinoline series.

10. A photographic gelatino-silVer-halide developing-out emulsionsensitized with a supersensitizing combination of at least one acidcarbocyanine dye selected from the group consisting of those representedby the following general formula:

wherein R represents a member selected from the group consisting of ahydrogen atom, a methyl group and an ethyl group, and Z and Z1 eachrepresents the non-metallic atoms necessary to complete a heterocyclicnucleus of the benzothiazole series, said heterocyclic nucleuscontaining, in addition to the carbon atoms, the nitrogen atom and thesulfur atom in the heterocyclic ring, no atoms other than those selectedfrom the group consisting of hydrogen atoms, carbon atoms, oXygen atomsand halogen atoms, together with at least one styryl base selected fromthe group consisting of those represented by the following generalformula:

wherein Z2 represents the non-metallic atoms necessary to complete aheterocyclic nucleus of the benzothiazole series, said heterocyclicnucleus containing in addition to the carbon atoms, the nitrogen atomand the sulfur atom in the heterocyclic ring no atoms other than thoseselected from the group consisting of hydrogen atoms, carbon atoms,oxygen atoms and halogen atoms, and Rz and lR3 each represents a primaryalkyl group of the formula CdHzd+1 wherein d represents a positiveinteger of from 1 to 4. Y

Y11. A photograpc(gelatino-silver-halide emul sion sensitized with asupersensitizing combination of anhydro-'5,5dichloro9-ethyl-3,3'-di--sulfoethylthiacarbocyanine hydroxide together with 2-(p-diethylaminostyryl) benzothiazole.

12. A photographic gelatino-silver-halide emulsion sensitized with asupersensitizing combination of at least one acid carbocyanine dyeselected from the group consisting of those represented by the followinggeneral formula:

17 wherein R1 represents a primary alkyl group of the formula CdH2fz+1wherein d represents a positive integer of from 1 to 4, Z represents thenonmetallio atoms necessary to complete a heterocyclic nucleus of thebenzothiazole series, said heterocyclic nucleus containing in additionto the carbon atoms, the nitrogen atom and the sulfur atom in theheterocyclic ring no atoms other than hydrogen atoms, carbon atoms,oxygen atoms and halogen atoms, and Z1 represents the non-metallic atomsnecessary to complete a heterocyclic nucleus of the quinoline series,said heterocyclic nucleus of the quinoline series containing, inaddition to the carbon atoms and the nitrogen atom in the heterocyclicring, no atoms other than hydrogen atoms, carbon atoms, oxygen atoms andhalogen atoms, together with at least one styryl base selected from thegroup consisting of those represented by the following general for- Ywherein Z2 represents the non-metallic atoms necessary to complete aheterocyclic nucleus of the benzothiazole series, said heterocyclicnucleus containing in addition to the carbon atoms, the nitrogen atomand the sulfur atom in the heterocyclic ring no atoms other than thoseselected from the group consisting of hydrogen atoms, carbon atoms,oxygen atoms and halogen atoms, and R2 and R3 each represents a primaryalkyl group of the formula CaH2d+1 wherein d represents a positiveinteger of from 1 to 4.

13. A photographic gelatino-silver-halide emulsion sensitized with asupersensitizing combination ofanhydro-5-chloro-1-ethyl-B-B-sulfoethylthia-2'carbocyanine hydroxidetogether with 2- p-diethylaminostyryl) benzothiazole.

14. A photographic gelatino-silver-halide emulsion sensitized with asupersensitizing combination of at least one acid carbocyanine dyeselected from the group consisting of those represented by the followinggeneral formula:

z R z R 1 (lj 6 HooC-CH-CHPN- =CH- =cH =N wherein R represents a memberselected from the group consisting of a hydrogen atom, a methyl groupand an ethyl group, R1 represents a primary alkyl group of the formulaCdHzd+1 wherein d represents a positive integer of from 1 to 4, Xrepresents an anion, Z represents the non-metallic atoms necessary tocomplete a heterocyclic nucleus of the benzothiazole series, saidheterocyclic nucleus containing, in addition to the carbon atoms thenitrogen atom and the sulfur atom in the heterocyclic ring, no atomsother than those selected from the group consisting of hydrogen atoms,carbon atoms, oxygen atoms and halogen atoms, and Z1 represents thenon-metallic atoms necessary to complete a heterocyclic nucleus of thequinoline series, said heterocyclic nucleus of the quinoline seriescontaining in addition to the carbon atoms and the nitrogen atom in theheterocyclic ring, no atoms other than hydrogen atoms, carbon atoms,oxygen atoms-and halogen atoms, together with at least one styryl baseselected from the group consisting of those represented by the followinggeneral formula:

wherein Z2 represents the non-metallic atoms necessary to complete aheterocyclic nucleus of the benzothiazole series, said heterocyclicnucleus containing in addition to the carbon atoms, the nitrogen atomand the sulfur atom in the heterocyclic ring no atoms other than thoseselected from the group consisting of hydrogen atoms, carbon atoms,oxygen atoms and halogen atoms, and R2 and R3 each represents a primaryalkyl group of the formula Cdl-12H1 wherein d represents a positiveinteger of from 1 to 4.

15. A photographic gelatine-silver-halide emulsion sensitized with asupersensitizing combination of S--carboxyethyl-l-ethylthia2carbocyanine iodide together with 2-(p-diethylaminostyryl) benzothiazole.

BURT I-I. CARROLL. J OI-IN SPENCE.

No references cited.

1. A PHOTOGRAPHIC SILVER HALIDE EMULSION SENSITIZED WITH ASUPERSENSITIZING COMBINATION OF AT LEAST ONE SENSITIZING ACIDCARBOCYANINE DYE SELECTED FROM THE GROUP CONSISTING OF THOSE REPREBY THEFOLLOWING THREE GENERAL FORMULAS: